Lexmark printer some colours not working

[amonty1144]

I have a lexmark printer z645,when I print some of the colours don't work, on the alignment test, the bottom line was missing completely. I've cleaned the heads twice but now the message is I may need to replace the ink cartridge as there are still missing itmes of print, namely blue. The catridge is half full or half empty, depending on how you look at it
Any other helpful hints before I throw it out of the window. Please be aware I'm not very technically minded and may fix it with a hammer lol
Thanks

[ianmunt]

Could be one colour has run out Try removing the cartridge and looking at the base where the ink comes out,can you see traces of all colours on the surface?If not suspect it is a case of replacement.You could try holding a damp tissue against the print head for a minute or two,then replacing in the printer and giving it another try.

[Hymie]

This is a common problem with inkjet printers (which is why I replaced mine with a cheap laser printer) � rather than replace what you believe to be a healthy cartridge, try this technique:-

Invert the cartridge and place one or two drops of clear solvent on the ink aperture, gently push a pin into the aperture, which should cause a capillary effect and the solvent drop will disappear into the inkjet cartridge. Replace the cartridge in the printer, and more often than not, it will start working again.

As for the solvent medium, I have used whatever is at hand; IPA (as used for cleaning tape heads) and petrol have both worked for me.